Lesson 2

Discover

 

Take a look around and you will see that there are many different types of quadrilaterals. Are you aware of the properties that make each type of quadrilateral unique? Complete Try This 1 to explore some of the properties of quadrilaterals and discover the names given to specific quadrilaterals.

 

Try This 1

 

Open Quadrilateral Demonstration Applet. Follow the instructions given in the questions. Analyze each constructed quadrilateral. Record your findings in a table like the one shown after each set of instructions.

 

1. Click and drag the corners of the quadrilateral until all side lengths are equal and each enclosed angle is 90°. Look above the quadrilateral. What specific name is given to this shape? Record this name in the first column of the table, and complete the rest of the information about this quadrilateral.
2. Move the top right and bottom right corners to the right so each angle is 90°. Record the name and information in the table.
3. Move the top right corner left and then move the top left corner to the right, keeping the top and bottom lines parallel. Record the name and information in the table.
4. Move the corners so the top and bottom are the same length and parallel. Adjust the left and right sides so they are the same length and parallel. Make sure the enclosed angles are not 90°. Record the name and information in the table.
5. Move the corners so all sides are equal and the enclosed angles are not 90°. Record the name and information in the table.
6. Move a corner away from the centre of the quadrilateral until two sides are equal and the other two sides are equal. Record the name and information in the table.
   
   

   Type of Quadrilateral	Pairs of Equal Sides (opposite or adjacent)	Number of Equal Sides	Pairs of Parallel Sides	Number of Equal Angles (right angles or not right angles)

Save your responses in your course folder.

 

Share 1

 

With a partner or in a group, share your responses to Try This 1 and address the following questions:

1. In any given quadrilateral, what is the sum of the interior angles?
2. Trapezoids can be classified as right trapezoids or isosceles trapezoids. From your knowledge of triangles and the terms right and isosceles, determine when a trapezoid is right or isosceles.

If required, place a summary of your discussion in your course folder.